Buggy code:
case IProblem . OverridingDeprecatedMethod : case IProblem . UsingDeprecatedType : case IProblem . UsingDeprecatedMethod : case IProblem . UsingDeprecatedConstructor : case IProblem . UsingDeprecatedField : return this . options . getSeverity ( CompilerOptions . UsingDeprecatedAPI ) ; case IProblem . LocalVariableIsNeverUsed : return this . options . getSeverity ( CompilerOptions . UnusedLocalVariable ) ; case IProblem . ArgumentIsNeverUsed : return this . options . getSeverity ( CompilerOptions . UnusedArgument ) ; case IProblem . NoImplicitStringConversionForCharArrayExpression : return this . options . getSeverity ( CompilerOptions . NoImplicitStringConversion ) ; case IProblem . NeedToEmulateFieldReadAccess : case IProblem . NeedToEmulateFieldWriteAccess : case IProblem . NeedToEmulateMethodAccess : case IProblem . NeedToEmulateConstructorAccess : return this . options . getSeverity ( CompilerOptions . AccessEmulation ) ; case IProblem . NonExternalizedStringLiteral : return this . options . getSeverity ( CompilerOptions . NonExternalizedString ) ; case IProblem . UseAssertAsAnIdentifier : return this . options . getSeverity ( CompilerOptions . AssertUsedAsAnIdentifier ) ; case IProblem . UseEnumAsAnIdentifier : return this . options . getSeverity ( CompilerOptions . EnumUsedAsAnIdentifier ) ; case IProblem . NonStaticAccessToStaticMethod : case IProblem . NonStaticAccessToStaticField : return this . options . getSeverity ( CompilerOptions . NonStaticAccessToStatic ) ; case IProblem . IndirectAccessToStaticMethod : case IProblem . IndirectAccessToStaticField : case IProblem . IndirectAccessToStaticType : return this . options . getSeverity ( CompilerOptions . IndirectStaticAccess ) ; case IProblem . AssignmentHasNoEffect : return this . options . getSeverity ( CompilerOptions . NoEffectAssignment ) ; case IProblem . UnusedPrivateConstructor : case IProblem . UnusedPrivateMethod : case IProblem . UnusedPrivateField : case IProblem . UnusedPrivateType : return this . options . getSeverity ( CompilerOptions . UnusedPrivateMember ) ; case IProblem . Task : return Warning ; case IProblem . LocalVariableHidingLocalVariable : case IProblem . LocalVariableHidingField : case IProblem . ArgumentHidingLocalVariable : case IProblem . ArgumentHidingField : return this . options . getSeverity ( CompilerOptions . LocalVariableHiding ) ; case IProblem . FieldHidingLocalVariable : case IProblem . FieldHidingField : return this . options . getSeverity ( CompilerOptions . FieldHiding ) ; case IProblem . PossibleAccidentalBooleanAssignment : return this . options . getSeverity ( CompilerOptions . AccidentalBooleanAssign ) ; case IProblem . SuperfluousSemicolon : case IProblem . EmptyControlFlowStatement : return this . options . getSeverity ( CompilerOptions . EmptyStatement ) ; case IProblem . UndocumentedEmptyBlock : return this . options . getSeverity ( CompilerOptions . UndocumentedEmptyBlock ) ; case IProblem . UnnecessaryCast : case IProblem . UnnecessaryArgumentCast : case IProblem . UnnecessaryInstanceof : return this . options . getSeverity ( CompilerOptions . UnnecessaryTypeCheck ) ; case IProblem . FinallyMustCompleteNormally : return this . options . getSeverity ( CompilerOptions . FinallyBlockNotCompleting ) ; case IProblem . UnusedMethodDeclaredThrownException : case IProblem . UnusedConstructorDeclaredThrownException : return this . options . getSeverity ( CompilerOptions . UnusedDeclaredThrownException ) ; case IProblem . UnqualifiedFieldAccess : return this . options . getSeverity ( CompilerOptions . UnqualifiedFieldAccess ) ; case IProblem . UnnecessaryElse : return this . options . getSeverity ( CompilerOptions . UnnecessaryElse ) ; case IProblem . UnsafeRawConstructorInvocation : case IProblem . UnsafeRawMethodInvocation : case UnsafeRawConversion : case IProblem . UnsafeRawFieldAssignment : case IProblem . UnsafeGenericCast : case IProblem . UnsafeReturnTypeOverride : return this . options . getSeverity ( UnsafeTypeOperation ) ; case IProblem . FinalBoundForTypeVariable : return this . options . getSeverity ( CompilerOptions . FinalParameterBound ) ; case IProblem . MissingSerialVersion : return this . options . getSeverity ( CompilerOptions . MissingSerialVersion ) ; case IProblem . ForbiddenReference : return this . options . getSeverity ( CompilerOptions . ForbiddenReference ) ; case InexactParameterToVarargsConstructor : case InexactParameterToVarargsMethod : <START_BUG> return Warning ; <END_BUG> case IProblem . JavadocUnexpectedTag : case IProblem . JavadocDuplicateReturnTag : case IProblem . JavadocInvalidThrowsClass : case JavadocInvalidReference : case IProblem . JavadocMalformedSeeReference : case IProblem . JavadocInvalidSeeHref : case IProblem . JavadocInvalidSeeArgs : case IProblem . JavadocInvalidTag : case IProblem . JavadocUnterminatedInlineTag : case IProblem . JavadocMissingHashCharacter : case IProblem . JavadocEmptyReturnTag : case IProblem . JavadocUnexpectedText : if ( this . options . docCommentSupport ) { return this . options . getSeverity ( CompilerOptions . InvalidJavadoc ) ; } else { return ProblemSeverities . Ignore ; } case IProblem . JavadocInvalidParamName : case IProblem . JavadocDuplicateParamName : case IProblem . JavadocMissingParamName : case IProblem . JavadocInvalidThrowsClassName : case IProblem . JavadocDuplicateThrowsClassName : case IProblem . JavadocMissingThrowsClassName : case JavadocMissingReference : case IProblem . JavadocInvalidValueReference : case IProblem . JavadocUndefinedField : case IProblem . JavadocAmbiguousField : case IProblem . JavadocUndefinedConstructor : case IProblem . JavadocAmbiguousConstructor : case IProblem . JavadocUndefinedMethod : case IProblem . JavadocAmbiguousMethod : case IProblem . JavadocAmbiguousMethodReference : case IProblem . JavadocParameterMismatch : case IProblem . JavadocUndefinedType : case IProblem . JavadocAmbiguousType : case IProblem . JavadocInternalTypeNameProvided : case IProblem . JavadocNoMessageSendOnArrayType : case IProblem . JavadocNoMessageSendOnBaseType : case IProblem . JavadocInheritedMethodHidesEnclosingName : case IProblem . JavadocInheritedFieldHidesEnclosingName : case IProblem . JavadocInheritedNameHidesEnclosingTypeName : if ( ( this . options . docCommentSupport ) && ( this . options . reportInvalidJavadocTags ) ) { return this . options . getSeverity ( CompilerOptions . InvalidJavadoc ) ; } return ProblemSeverities . Ignore ; case IProblem . JavadocUsingDeprecatedField : case IProblem . JavadocUsingDeprecatedConstructor : case IProblem . JavadocUsingDeprecatedMethod : case IProblem . JavadocUsingDeprecatedType : if ( ( ( this . options . docCommentSupport ) && ( this . options . reportInvalidJavadocTags ) ) && ( this . options . reportInvalidJavadocTagsDeprecatedRef ) ) { return this . options . getSeverity ( CompilerOptions . InvalidJavadoc ) ; } return ProblemSeverities . Ignore ; case IProblem . JavadocNotVisibleField : case IProblem . JavadocNotVisibleConstructor : case IProblem . JavadocNotVisibleMethod : case IProblem . JavadocNotVisibleType : if ( ( ( this . options . docCommentSupport ) && ( this . options . reportInvalidJavadocTags ) ) && ( this . options . reportInvalidJavadocTagsNotVisibleRef ) ) { return this . options . getSeverity ( CompilerOptions . InvalidJavadoc ) ; } return ProblemSeverities . Ignore ; case IProblem . JavadocMissingParamTag : case IProblem . JavadocMissingReturnTag : case IProblem . JavadocMissingThrowsTag : if ( this . options . docCommentSupport ) { return this . options . getSeverity ( CompilerOptions . MissingJavadocTags ) ;

Fix:
return this . options . getSeverity ( InexactVarargsArgument ) ;